1. Field of the Invention
The present invention relates to a thread wound golf ball.
2. Description of the Related Art
A thread wound golf ball is obtained by winding a thread rubber around a solid or liquid rubber center to form a thread rubber layer and covering the thread rubber layer with a cover material (e.g. ionomer, balata. etc.). As the solid center, a vulcanized rubber of butadiene is conventionally used, which has high hardness and low compression deformation. In a golf ball using such a conventional center, the formation of spin is large and launch angle is small and, therefore, the golf ball is disadvantageous in view of flying distance. Further, the curving of the flight of the golf ball is too large and it is sometimes hard to control.
On the other hand, a liquid center has high compression deformation. In a golf ball using the liquid center, the formation of spin is small and launch angle is large and, therefore, the golf ball is advantageous in view of flying distance in comparison with a conventional solid center. In golf balls having liquid center, however, the production process is complicated. Also, there is a problem of safety, for example, when a ball is cut by a knife or a cutter, a liquid is sprayed out, which may result in loss of eyesight.